Field
The present application relates to a lighting device for a medical or dental instrument, in particular for an instrument head of such an instrument, having at least one semiconductor element which is designed for emission of electromagnetic radiation, in particular radiation in the visible wavelength range.
Description of Prior Art
A lighting device for a medical or dental instrument is known from German Utility Model DE 20 202 020 763 U1, for example. This lighting device comprises a metallic cap with a light-dispensing window and a metallic socket welded to the metallic cap so that an encapsulated interior is formed by the cap and the socket. An optical semiconductor element (LED) for generating light is mounted on the socket and provided in this interior. Two metallic electric contacts penetrate through the socket and are connected to the optical semiconductor element for the purpose of power supply. The two contacts are sealed in glass in the area of the socket. Such a design of the lighting device has proven successful in practice and provides excellent protection of the optical semiconductor element accommodated in the encapsulated interior from aggressive environmental conditions, for example, in cleaning the instrument in a sterilizer and from soiling. However, the encapsulation causes the lighting device to be larger and thus also increases the space required for the lighting device in or on the instrument.
There is thus the problem of creating a lighting device having reduced external dimensions while retaining the well-proven design encompassing the socket, the cap, the light-dispensing window and the encapsulated interior in order to enable or facilitate the arrangement of one or more such lighting devices in or on the medical or dental, instrument or on certain sections or components of an instrument.
An instrument in the form of a dental handpiece with a lighting device is known from the patent application EP 1 093 765 A2, for example. According to one embodiment, the handpiece has a head, on whose bottom side an opening is provided for dispensing of fluid, in particular air or water. In addition, a lighting device with semiconductor elements (LEDs) is provided on the head of the handpiece around an opening to receive a treatment tool. The lighting device with the semiconductor elements is shaped in the form of a horseshoe or a C-shape and thus has two free ends and a clearance between the two free ends. This clearance serves to accommodate the fluid-dispensing opening arranged on the bottom side of the handpiece head as well as an expansion volume of the fluid stream propagating from the fluid-dispensing opening in the form of a cone.
A section from which no radiation is emitted onto the treatment site is created by the clearance between the two free ends of the lighting device, which is a disadvantage, so that a smaller or less well-illuminated region is formed on the treatment site. This is a disadvantage in particular because an essentially uniform illumination to which the user's eye is adjusted is created on the treatment site due to the C-shaped design of the lighting device.
Thus another object is to create a lighting device with at least one semiconductor element for a medical or dental, instrument, in particular for an instrument head of such an instrument or to create a medical or dental, instrument or instrument head with such a lighting device while avoiding the aforementioned disadvantages. The lighting device should in particular be suitable for arranging it around a tool that can be connected to the instrument or to the instrument head and acts on a treatment site or around a receiving opening for such a tool on the instrument or the instrument head to achieve effective irradiation or illumination of the treatment site, and, additionally, to allow an effective supply of one or more treatment fluids to the treatment site.